Hospital bed equipment support apparatus

ABSTRACT

An equipment support for use with a patient assist apparatus having a signal source includes a receptacle adapted to mount to the patient assist apparatus having a plurality of contacts adapted to receive signals from the signal source and a cavity, and a support body or pole having an equipment mount on one end and a plug on the other end for being removably inserted into the cavity. The plug includes a plurality of contacts that are connected to conductors that extend through the support body to the equipment mount to provide the signals from the signal source to equipment mounted on the equipment mount. The plug contacts and receptacle contacts are arranged such that all of the plug contacts contact their corresponding receptacle contacts as the plug is inserted into the receptacle.

RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional PatentApplication Serial No. 60/314,483, filed Aug. 23, 2001, and U.S.Provisional Patent Application Serial No. 60/333,387, filed Nov. 26,2001, the disclosures of which are hereby expressly incorporated hereinby reference.

FIELD OF THE INVENTION

[0002] The present invention generally relates to devices for supportingequipment used with patient assist apparatuses, and more particularly toa device for supporting patient care equipment and providing electricalconnections thereto from a receptacle attached to the patient assistapparatus which removably receives the support.

BACKGROUND OF THE INVENTION

[0003] Patient assist apparatuses, such as hospital beds, are typicallyprovided with or connected to medical equipment, such as controlpendants, monitors/interface devices, etc. Conventional pendants aregenerally electrically connected to the control circuitry of the bed bya cable which permits placement of the pendant at various locations onthe bed. Interface devices are generally mounted to the side rails orthe head or foot board of the bed, and electrically hardwired to the bedelectronics.

[0004] It is desireable to have maximum flexibility in terms of locatingand relocating such medical equipment to accommodate access to thepatient by medical personnel, placement of other monitoring andtreatment equipment, and re-positioning of the patient. Whileconventional pendants are easily moved between various locations, thecable may become tangled, or otherwise impede access to the patient,placement of other equipment, and movement of the patient.

[0005] Additionally, interface devices may be difficult to use orinconviently located when provided at a fixed location on the bed. Forexample, if an interface device is mounted to a bed side rail which mustbe folded down, the interface may be rendered essentially useless. Ifthe interface is mounted to the foot board, medical personnel positionedat the head of the bed must relocate to use the interface.

SUMMARY OF THE INVENTION

[0006] The present invention provides an equipment support device foruse with a patient assist apparatus which may include a plurality ofreceptacles mounted at various locations on the apparatus for removablyreceiving a support body to which is mounted equipment, such as acontrol pendant and/or an interface device. The receptacles may includea cavity and a plurality of contacts extending into the cavity and beingconnected to the control circuitry of the apparatus. The support bodymay include a plug at one end having a plurality of contacts configuredto mate with the receptacle contacts when the plug is seated in thereceptacle cavity. Conductors extend from the plug contacts to theequipment mounted to the support body. Accordingly, medical personnelmay locate the equipment support device at any of the receptaclelocations around the patient assist apparatus by inserting the supportbody plug into the desired receptacle, thereby electrically connectingthe equipment mounted to the equipment support device to the apparatuscontrol circuitry and mechanically supporting the equipment in a desiredlocation.

[0007] In an alternate embodiment, the receptacles may include power andsignal windings that loop around the central cavity of the receptacle.These windings form one side of a pair of transformers, one forsupplying power to the support body, and one for supplying other signalsto the support body. The support body plug includes correspondingsecondary windings that complete the pair of transformer circuits, andare connected to conductors that supply power and other signals to theequipment mounted to the support body. In this embodiment, thereceptacle contacts and the plug contacts are eliminated. Power andother signals are provided to the equipment with electrical isolation.Additionally, a spring-loaded detent is provided in each of thereceptacles for cooperating with a lock ring on the support body plug tomechanically retain the plug in the receptacle when the plug is in aseated position.

[0008] The features of the present invention described above, as well asadditional features, will be readily apparent to those skilled in theart upon reference to the following description and the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009]FIG. 1 is a perspective view of a patient assist apparatus havinga plurality of equipment support apparatuses attached thereto.

[0010]FIG. 2A is a partially fragmented, side elevational view of aportion of an equipment support apparatus according to the presentinvention.

[0011]FIG. 2B is a top plan view of the equipment support apparatusshown in FIG. 2A.

[0012]FIG. 3 is a side elevational view of components of an equipmentsupport apparatus according to the present invention.

[0013]FIGS. 4A and 4B are perspective views of a receptacle of anequipment support apparatus according to the present invention.

[0014]FIG. 4C is a side elevational view of the receptacle shown inFIGS. 4A and 4B.

[0015]FIG. 4D is a top plan view of the receptacle shown in FIGS. 4A-C.

[0016]FIG. 5 is a partially fragmented, side elevational view, partly insection, of a portion of an equipment support apparatus according to thepresent invention.

[0017]FIGS. 6A and 6B are partially fragmented, side elevational views,partly in section, depicting the electrical connections of embodimentsof an equipment support apparatus according to the present invention.

[0018]FIG. 7A is a partially fragmented, side elevational view of aportion of another embodiment of an equipment support apparatusaccording to the present invention.

[0019]FIG. 7B is a top plan view of the equipment support apparatusshown in FIG. 7A.

[0020]FIGS. 8A and 8B are perspective views of another embodiment of areceptacle of an equipment support apparatus according to the presentinvention.

[0021]FIG. 8C is a side elevational view of the receptacle shown inFIGS. 8A and 8B.

[0022]FIG. 8D is a top plan view of the receptacle shown in FIGS. 8A-C.

[0023]FIG. 9 is a partially fragmented, side elevational view, partly insection, of a portion of another embodiment of an equipment supportapparatus according to the present invention.

[0024]FIG. 10A is an electrical schematic diagram of a portion of thecircuit of the equipment support apparatus shown in FIGS. 7-9.

[0025]FIG. 10B is an electrical schematic diagram of an alternate powerinput circuit to replace a portion of the circuit of FIG. 10A.

[0026] FIGS. 11A-C are side elevational views of alternate embodimentsof a receptacle of an equipment support apparatus according to thepresent invention.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[0027] The exemplary embodiments selected for description below are notintended to limit the invention to the precise forms disclosed. Instead,the embodiments have been selected for description to enable one ofordinary skill in the art to practice the invention.

[0028]FIG. 1 shows a hospital bed 10 that has a variety of conventionalcomponents including a frame 12. Three embodiments of an equipmentsupport apparatus according to the present invention 14A-C are shownattached to frame 12. Equipment supports 14A, 14B, and 14C differ invarious ways which will be described in detail below. In general,however, each equipment support 14A, 14B, and 14C includes a supportbody 16A-C, a plug 18A-C at one end 20A-C of support body 16A-C, and areceptacle 22A-C attached to frame 12.

[0029] Support body 16A of equipment support 14A may be formed from agenerally rigid hollow pole, and includes an equipment end 26A oppositeend 20A. Equipment support 14A also includes an equipment mount 28Aconnected to equipment end 26A of support body 16A. A goose neck orflexible portion 30A having a free end 32A is also connected toequipment end 26A of support body 16A. An interface 34A is physicallyand electrically connected to equipment mount 28A as is furtherdescribed below. Interface 34A (and interface 34C) may be a display, acontrol panel, or any other type of interface or monitor. Similarly, apendant 36A is physically and electrically connected to free end 32A offlexible portion 30A as is further described below. The position ofpendant 36A may be adjusted by moving the pendant within the range ofpositions provided by the flexibility of flexible portion 30A. It shouldbe understood that equipment mount 28A may be movably or adjustablymounted on support body 16A such that interface 34A may be movedupwardly and downwardly on support body 16A, rotated about support body16A, and tilted relative to support body 16A. If such adjustability isprovided, then the electrical conductors or wires connecting equipmentmount 28A (and interface 34A) to plug 18A, further described below, mayextend through an opening or slot in support body 16A and havesufficient slack and/or flexibility to accommodate the full range ofadjustment of equipment mount 28A.

[0030] Equipment support 14B similarly includes a support body 16B withan equipment end 26B, a flexible portion 30B having a free end 32B, anda pendant 36B mechanically and electrically connected to free end 32B offlexible portion 30B. Unlike support body 16A, support body 16B does notinclude an equipment mount or interface. Also, support body 16B includesa first section 25B and a second section 27B. First section 25B isconnected to second section 27B at a telescopic joint 29B. Telescopicjoint 29B permits adjustment of the height of pendant 36B above bed 10.In other words, as one of first section 25B or second 27B istelescopically received within the other section, the overall height ofsupport body 16B is reduced. As will be further described below,conductors (not shown) extend between pendant 36B and plug 18B (throughflexible portion 30B and support body 16B) to permit communicationbetween electronics on pendant 36B and other portions of bed 10.Obviously, the conductors (not shown) connecting pendant 36B to plug 18Bmust have sufficient slack and/or flexibility to accommodate the fullrange of adjustment of support body 16B. Additionally, the position ofpendant 36B may be adjusted within the range of positions provided byflexible portion 30B.

[0031] Equipment support 14C also includes a support body 16C with anequipment mount (not shown) for mounting an interface 34C at equipmentend 26C of support body 16C. A standard, telescopically extendable IVbag hook 36C is received by equipment end 26C of support body 16C. Likesupport bodies 16A and 16B, support body 16C includes conductors (notshown) which extend between the equipment mount (not shown) and plug18C.

[0032] Also shown in FIG. 1 is a fourth receptacle 22D mounted to theperimeter of frame 12. Additional receptacles may be mounted at otherlocations on frame 12 to permit relocation of any of equipment supports14AC. As is further described below, electrical contacts in receptacles22A-D provide power and other signals to interfaces 34A, 34C, andpendants 36A, 36B. When receptacles 22A-D are mounted to frame 12, theseelectrical contacts may be hard-wired to the control circuitry of bed10.

[0033]FIGS. 2A and 2B show a plug according to the present invention.Since plugs 18A-C of equipment supports 14A-C are identical, only oneplug is described below. Plug 18A generally includes a stop 40 which isconnected to end 20A of support body 16A, and a substantiallycylindrical, elongated body 42 including an end 44 connected to stop 40and an end 46 connected to a tip 48. Tip 48 is formed of anon-conductive material and includes a slightly tapered outer surface 98which terminates in a rounded dome 100. As shown in FIG. 2A, supportbody 16A, stop 40, plug body 42, and tip 48 are substantially coaxial.

[0034] Stop 40 is an annular, ring-shaped member having a centralopening 50 (FIG. 2B) that receives support body 16A, an upper surface52, a lower surface 54, and an outer surface 56 which tapers slightlyfrom upper surface 52 to lower surface 54. A cylindrical extension 58protrudes from lower surface 54 of stop 40 and is connected to end 44 ofplug body 42.

[0035] Plug body 42 includes insulators 60, 62, 64, 66, and contacts 68,70, 72, 74. As best shown in FIG. 3, insulators 60, 62, 64, 66 aresubstantially cylindrical with central openings 76, 78, 80, 82,respectively. As should be apparent from the figures, spacers 60, 62,64, 66 include annular members having one of two lengths. Specifically,spacers 60 and 66 are identical in length and shorter than spacer 64.Spacer 62 is an assembly of four spacer sections 84, 86, 88, 90. Spacersections 86 and 90 are identical to spacers 60 and 66. Spacer sections84 and 88 are identical to spacer 64. Accordingly, spacers having any ofa variety of different lengths may be assembled using two standardlength spacer sections. It should be understood that stop 40, tip 48,and all of the components of plug body 42 may be assembled in any of avariety of ways. For example, each piece could include appropriatelythreaded male and female portions (not shown), or simply be formed asslip rings to be received over a common inner sleeve (not shown).

[0036] Referring again to FIG. 2A, spacers 60, 62, 64, 66 havesubstantially the same outer diameter D₂, which is smaller than theouter diameter D₁ of stop 40. First contact 68 is located between spacer60 and spacer 62. Second contact 70 is located between spacer 62 andspacer 64. Third contact 72 is located between spacer 64 and spacer 66.Finally, fourth contact 74 is located between spacer 66 and tip 48.

[0037] Contacts 68, 70, 72, and 74 are substantially identical.Therefore, only one is labeled in FIG. 2A. Each of contacts 68, 70, 72,and 74 include an annular portion 92 and a retention ring 94 having adiameter D₃ which is larger than diameter D₂ and smaller than diameterD₁. Retention rings 94 have a chamfered upper edge 96 and a chamferedlower edge 98. Retention rings 94 may be either conductive ornon-conductive. Likewise, portions 92 may be either conductive ornon-conductive. In the embodiment described, portions 92 arenon-conductive and retention rings 94 are conductive. As shown in FIG.2A, the spacings S₁, S₂, S₃ between retention rings 94 of contacts 68,70, 72, and 74 are all different as a result of the different lengths ofspacers 62, 64, and 66. This prevents shorting and erroneous connectionsduring insertion and removal of plug 18A into and out of receptacle 22Aas will be further described below.

[0038] Each retention ring 94 of contacts 68, 70, 72, and 74 isconnected to a respective conductor (FIGS. 6A and 6B) which extendswithin the central opening formed through the spacers and conductors,central opening 50 of stop 40, and a central opening 162 of support body16A.

[0039] An illustrative receptacle 22A is shown in FIGS. 4A-4D.Receptacle 22A generally includes a first half 102 and a second half 104that may be assembled separately and attached together at interface 106using any of a variety of conventional attachment techniques. Oncejoined, halves 102, 104 form a six-sided body having an upper surface108, a lower surface 110 and side surfaces 112, 114, 116, 118. A centralopening 120 is formed in upper surface 108. A cavity generally referredto by numeral 122 extends from opening 120 through receptacle 22A tobottom surface 110. As best shown in FIG. 4C, cavity 122 includes anenlarged diameter portion 124 having a cylindrical, slightly taperedside surface 126 and a shoulder surface 128 which is substantiallyparallel to upper surface 108 of receptacle 22A. Cavity 122 furtherincludes an elongated central portion 130, a tapered lower portion 132,and a lower opening 134 formed in lower surface 110 of receptacle 22A.Cavity 122 is generally cylindrical and includes a central axis 136.

[0040] As best shown in FIGS. 4A-4D, half 102 of receptacle 22A includesa pair of bores 138, 140 which are substantially vertically aligned onside surface 112 and extend into cavity 122. Similarly, half 104 ofreceptacle 22A includes bores 142, 144 which are substantiallyvertically aligned and extend from side surface 116 into cavity 122. Asbest shown in FIG. 4D, bores 138, 140, 142, 144 lie in substantially thesame plane when halves 102, 104 are assembled. As best shown in FIG. 4C,a first detent contact 146 is installed in bore 142, a second detentcontact 148 is installed in bore 138, a third detent contact 150 isinstalled in bore 144, and a fourth detent contact 152 is installed inbore 140. Detent contacts 146, 148, 150, 152 may be conventional,off-the-shelf ball and spring detent assemblies. Each detent contact isconnected via a wire (not shown) to the control circuitry of bed 10.

[0041] Referring now to FIG. 5, plug 18A is shown in a seated positionwherein substantially the entire plug body 42 is inserted into cavity122. When plug 18A is so positioned within cavity 122, detent contacts146, 148, 150, and 152 of receptacle 22A make electrical contact withretention rings 94 of plug body contacts 68, 70, 72, 74, respectively.Bore 142 and detent contact 146 are spaced a distance X, from uppersurface 108 of receptacle 22A. Similarly, bore 138 and detent contact148 are spaced a distance X₂ from upper surface 108, bore 144 and detentcontact 150 are spaced a distance X₃ from upper surface 108, and bore140 and detent contact 152 are spaced a distance X₄ from upper surface108. The difference between distances X₂ and X₁ corresponds to spacingS₁. Likewise, the difference between distances X₃ and X₂ corresponds tospacing S₂. Finally, the difference between distances X₄ and X₃corresponds to spacing S₃. Since detent contacts 146, 148, 150, 152 arespaced to correspond with the spacings S₁, S₂, S₃ between plug contacts68, 70, 72, 74, when plug 18A is in the seated position shown in FIG. 5,electrical connections are made between detent contact 146 and contact68, detent contact 148 and contact 70, detent contact 150 and contact72, and detent contact 152 and contact 74. Because spacings S₁, S₂, S₃are different from one another, as plug 18A is inserted downwardly intocavity 122 of receptacle 22A, all of detent contacts 146, 148, 150, 152simultaneously contact their respective plug contacts 68, 70, 72, 74when plug 18A substantially reaches the seated position, but not duringinsertion or removal of plug 18A.

[0042] As should be apparent from FIG. 5, as plug 18A is moveddownwardly, the balls of detent contacts 146, 148, 150, 152 are urgedoutwardly from central axis 136 by rings 94 of plug contacts 68, 70, 72,74. Electrical contact is established as soon as rings 94 contact theballs of detent contacts 146, 148, 150, 152. As a ring 94 moves past adetent contact 146, 148, 150, 152, the ball of the detent contact camsover chamfered edge 98 and down chamfered edge 96 of ring 94. When plug18A is in the seated position, each of the balls is spring biasedoutwardly against portions 92. Rings 94 remain in electrical contactwith the balls and provide a locking function to resist removal of plug18A upwardly out of cavity 122. Specifically, sufficient upward forcemust be applied to support body 16A to overcome the force exertedagainst plug 18A by the balls, which force resists upward movement asthe balls cam over chamfered edge 96 of retention rings 94. As shown inFIG. 5, detent contacts 146, 150 are opposed to detent contacts 148, 152so that the spring force urging the balls of one pair of the detentcontacts is in substantial opposition to the spring force urging theballs of the other pair of detent contacts toward plug body 42, therebyproviding a better “grip” on plug 18A. Additionally, it should be notedthat by providing spring biased detent contacts 146, 148, 150, 152, thepresent invention may provide more reliable electrical connections thanwould a receptacle and plug assembly using friction fit connections.

[0043] As should also be apparent from FIG. 5, as plug 18A is inserteddownwardly in cavity 122, tip 48 guides plug 18A and maintainssubstantial vertical alignment along central axis 136 of cavity 122. Asplug 18A approaches the seated position shown in FIG. 5, dome surface100 and tapered surface 98 of tip 48 guide plug 18A along tapered lowerportion 132 and through opening 134. Further downward movement of plug18A is prevented by stop 40. Specifically, lower surface 54 of stop 40engages shoulder surface 128 of enlarged diameter portion 124 of cavity122, thereby preventing further downward movement. Tapered surface 56 ofstop 40 cooperates with tapered side surface 126 of cavity 122 to centerand guide plug 18A into cavity 122 as plug 18A approaches the seatedposition.

[0044] Referring now to FIGS. 6A and 6B, wires or conductors 160 areconnected to plug contacts 68, 70, 72, and 74, respectively.Specifically, each conductor 160 is connected to a separate ring 94 ofcontacts 68, 70, 72, 74. FIG. 6A illustrates the routing of conductors160 for equipment support 14A, also shown in FIG. 1. Conductors 160extend through central opening 162 in support body 16A, throughequipment end 26A and a hollow interior 164 of flexible portion 30A topendant 36A. Conductors 160 may provide power and other signals topendant 36A from receptacle 18A, and pendant 36A may provide signalsthrough conductors 160 to receptacle 18A. For example, a patient maypress a call button on pendant 36A which sends a signal throughconductors 160 to receptacle 18A and equipment associated with bed 10according to principles well known in the art. Conductors 166 extendfrom pendant 36A through hollow interior 164 of flexible portion 30A,central opening 162 of support body 16A, and an opening 168 formed insupport body 16A to equipment mount 28A. Conductors 166 are connected tointerface 34A at equipment mount 28A using appropriate connectors.Accordingly, power and other signals may be routed between receptacle18A and interface 34A through equipment mount 28A and pendant 36A.

[0045]FIG. 6B reflects the basic conductor routing of equipment support14C (FIG. 1) which does not include a pendant. IV bag hook 36C ofequipment support 14C, shown in FIG. 1, is not shown in FIG. 6B. FIG. 6Bshows conductors 160 from plug contacts 68, 70, 72, 74 routed directlyto interface 34C through central opening 162 of support body 16C,opening 168, and equipment mount 28C. It should be understood from theforegoing that the conductor routing of equipment support 14B (whichincludes only a pendant and no interface) is the same as that shown inFIG. 6A except that conductors 166 are unnecessary.

[0046] FIGS. 7-10 depict an alternate embodiment of an equipment supportapparatus according to the present invention. Various components of thealternate embodiment described below are similar to the componentsdescribed with reference to the previous figures. Accordingly, thereference designations of like components have been retained, butincreased by 200. FIGS. 7A and 7B show an alternate embodiment of a plug218 according to the present invention. Plug 218 generally includes astop 240 that is connected to an end 220 of support body 216, and asubstantially cylindrical, elongated body 242 including an end 244connected to stop 240 and an end 246 connected to a tip 248. Body 242,stop 240, and tip 248 are formed of a non-conductive material. Tip 248includes a slightly tapered outer surface 298 which terminates in arounded dome 300. As shown, support body 216, stop 240, plug body 242,and tip 248 are substantially coaxial.

[0047] Stop 240 is an annular, ring-shaped member having a centralopening 250 (FIG. 7B), an upper surface 252, a lower surface 254, and anouter surface 256 which tapers slightly from upper surface 252 to lowersurface 254. A cylindrical extension 258 extends from lower surface 254to tip 248, and carries an increased diameter retention ring 274. InFIG. 7A, retention ring 274 is shown positioned adjacent tip 248. Itshould be understood, however, that retention ring 274 may be locatedanywhere along the length of extension 258.

[0048] A first conductor 291 extends from end P_(H2), through supportbody 216 and central opening 250 of plug 218 to a location withinextension 258 of plug body 242. Conductor 291 forms a loop 261 embeddedwithin the non-conductive material of extension 258 adjacent the outersurface of extension 258. The other end of conductor 291 extends backthrough central opening 250 and support body 216 to end P_(L2).Similarly, a second conductor 293 extends from end S_(H2), throughsupport body 216 and central opening 250 to form a loop 259 withinextension 258 adjacent the outer surface of extension 258. Conductor 293also extends back through opening 250 to end S_(L2). As will be furtherdescribed below, loops 259, 261 each form one side of a transformercircuit.

[0049] FIGS. 8A-8D show an alternate embodiment of a receptacle 222according to the present invention for receiving plug 218 describedabove. Receptacle 222 differs from receptacle 22A of FIGS. 4A-D in thatit does not include a plurality of electrically conductive detentcontacts 146, 148, 150, 152, but instead includes conductive loops 249,251 as described below. Receptacle 222 includes halves 202, 204 whichare substantially the same as halves 102, 104 of receptacle 22A (exceptfor bores 142, 144, 146, 148) and therefore not described in detail withreference to FIGS. 8A-8D. Halves 202, 204 form a central cavity 322 thatextends substantially the entire length of receptacle 222 as best shownin FIG. 8C. Again, since cavity 322 is substantially the same as cavity122 of receptacle 22A, the various surfaces and portions of cavity 322are not repeated in the description of receptacle 222. Receptacle 222further includes a bore 340 that extends through half 204 from an outersurface of receptacle 222 to central cavity 322. A spring loaded detent352 is mounted within bore 340 such that a ball 341 of detent 352 (FIGS.8C and 8D) is biased partially into cavity 322.

[0050] A conductor 295 extends from end P_(H1) through an opening inreceptacle 222 to form a loop 251 about central cavity 322. The otherend of conductor 295 extends through another opening in receptacle 222to end P_(L1). Similarly, at another location within receptacle 222, asecond conductor 297 extends from end S_(H1) through an opening inreceptacle 222 to form a loop 249 about central cavity 322. The otherend of conductor 297 extends through another opening in receptacle 222to end S_(L1). Loops 249, 251 are embedded within the material ofreceptacle 222 just below the surface of cavity 322. In other words,loops 249, 251 are embedded into the inner, cylindrical wall of cavity322 such that loops 249, 251 do not contact plug 218 when plug 218 isinserted into receptacle 222.

[0051] Referring now to FIG. 9, plug 218 is shown in a seated positionwithin receptacle 222. As shown, loop 259 of plug 218 lies substantiallywithin the same plane as loop 249 of receptacle 222 such that the signalprovided on conductor 297 is inductively coupled from loop 249 to loop259 and conductor 293 having ends S_(L2) and S_(H2). Similarly, loop 261lies substantially within the plane as loop 251 such that the signalprovided on conductor 295 is inductively coupled from loop 251 to loop261 and conductor 291 having ends P_(H2) and P_(L2). In this manner,power and control signals are provided from receptacle 222 to equipmentsupport 216 even if dirt or other foreign material is built up in cavity322 or on plug 218. Additionally, electricity is provided fromreceptacle 222 to equipment support 216 without requiring exposed,electrically conductive contacts.

[0052] As shown in FIG. 9, when plug 218 is in the seated position, ball341 of detent 352 is urged outwardly toward extension 258 of plug 218above retention ring 274. The outward biasing force of the spring (notshown) on ball 341 resists upward movement of plug 218 throughinterference with retention ring 274. Accordingly, the possibility ofaccidental removal of equipment support 216 from receptacle 222 isreduced.

[0053]FIG. 10A shows a basic schematic diagram of one possible circuitfor supplying power from receptacle 222 to equipment support 216. An ACsource (V_(AC)) is provided externally to the equipment supportapparatus of the present invention. One side of supply V_(AC) isconnected to end P_(H1) of conductor 295, and the other side isconnected to end P_(L1). Loop 251 is formed between ends P_(H1) andP_(L1) to form one side of the transformer shown in FIG. 10A. As shown,loop 251 is formed within receptacle 222 as described above. Loop 261(the other side of the transformer) is formed within equipment support216 as described above. Conductor 291 from loop 261 extends to endsP_(H2), P_(L2) which are connected to a full-wave rectifier circuit 253and a voltage regulator 255 to provide a DC output in a manner that iswell-known to those skilled in the art. It should be understood that thesignals provided on conductor 297 extending between ends S_(H1) andS_(L1) may be implemented using the same circuit as that describedabove.

[0054]FIG. 10B shows an alternate embodiment of the circuit of FIG. 10A.Specifically, instead of an AC power supply (V_(AC)), the circuit ofFIG. 10B includes a DC power supply (V_(DC)) or a battery that isconnected in a conventional manner to an oscillator circuit 257. Theoutput of oscillator circuit 257 to nodes P_(H1) and P_(L1) is an ACsignal similar to that provided from the AC power supply (V_(AC)). Thissignal may be passed through a transformer as described with referenceto FIG. 10A, rectified by full wave rectifier 253, and regulated to forma DC signal at the output of regulator 255.

[0055] Referring now to FIGS. 11A-C, alternate embodiments of areceptacle of an equipment support apparatus according to the presentinvention are shown. Unlike receptacle 22A shown in FIGS. 4A-C, thereceptacles of these embodiments do not include detent contacts thatnormally extend into the central cavity of the receptacle. Instead, asfurther described below, the detent contacts of these embodiments areactuated or moved to contacting positions within the cavity as a resultof movement of plug 18A to the seated position within the cavity.Otherwise, several of the items shown in FIGS. 11A-C are similar toitems depicted in FIGS. 4A-C, and are referred to using referencedesignations that have been increased by 300.

[0056] As shown in FIG. 11A, receptacle 422A generally includes firsthalf 402A, second half 404A, and actuator 403. Like first half 102 ofreceptacle 22, first half 402A includes a pair of bores 438, 440 thatcontain detent contacts 448A, 452A, respectively. Similarly, second half404A includes bores 442, 444 that contain detent contacts 446A, 450A,respectively. Each detent contact 446A, 448A, 450A, 452A is identical.For simplicity, only detent contact 446A is labeled with referencedesignations. Each detent contact 446A, 448A, 450A, 452A includes a body405 having a cam surface 407 and a ball 409. Each body 405 is biased outof cavity 422, away from central axis 436 by a spring 411. First half402A further includes a channel 413 that extends upwardly within firsthalf 402A from an opening formed in bottom surface 410. Second half 404Aincludes a similar channel 415.

[0057] As shown, actuator 403 generally includes a first portion 417situated within channel 413 of first half 402A, a second portion 419situated within channel 415 of second half 404A, and an engagementportion 421 extending between first portion 417 and second portion 419.First portion 417 includes a first cam 423 having a first cam surface425 and a second cam 427 having a second cam surface 429. Second portion419 similarly includes a third cam 431 having a third cam surface 433and a fourth cam 435 having a fourth cam surface 437. Engagement portion421 includes a pair of angled segments 439, 441 and an engagementsegment 443.

[0058] When plug 18A is inserted into cavity 412, balls 409 of detentcontacts 446A, 448A, 450A, and 452A do not contact plug 18A because theballs are recessed into their respective bores 442, 438, 444, and 440.As plug 18A approaches the seated position, however, tip 48 engagesengagement segment 443 of actuator engagement portion 421. As plug 18Ais inserted farther downwardly, tip 48 moves actuator 403 downwardlysuch that first portion 417 and second portion 419 are moved downwardlyin channels 413, 415, respectively. As first portion 417 and secondportion 419 move downwardly, cam surfaces 425, 429, 433, and 437 of cams423, 427, 431, and 435 respectively engage cam surfaces 407 of detentcontacts 448A, 452A, 446A, 450A. As a result, detent contacts 446A,448A, 450A, 452A are urged inwardly toward plug 18A against the biasingforce of springs 411. Accordingly, when plug 18A is in the seatedposition, balls 409 of detent contacts 446A, 448A, 450A, 452A are inelectrical connection with rings 94 of plug contacts 68, 70, 72, and 74,respectively. As should be apparent from the foregoing, actuator 403 mayinclude a return mechanism such as a spring (not shown) to returnactuator 403 to the position shown in FIG. 11A when plug 18A is removedfrom receptacle 422A. Alternatively, springs 411 of detent contacts446A, 448A, 450A, and 452A may provide a sufficiently large biasingforce to cause cam surfaces 407 of detent contacts 446A, 448A, 450A, and452A to move along cam surfaces 433, 425, 437, 429 of cams 431, 423,435, and 427, respectively, thereby urging actuator 403 upwardly intothe position shown in FIG. 11A.

[0059] Referring now to FIG. 11B, another embodiment of a receptacle isshown. Receptacle 422B is generally similar to receptacle 422A, butincludes a two-piece actuator that does not extend out of the assembly.More specifically, first half 402B includes a modified channel 413B thatterminates at a lower end 445 rather than extending through bottomsurface 410. Additionally, channel 413B includes an opening 447 thatextends between channel 413B and cavity 422. Second half 404B similarlyincludes a modified channel 415B that terminates at a lower end 449 andincludes an opening 451.

[0060] Receptacle 422B further includes a first actuator 417B, a firstspring 453, a second actuator 419B, and a second spring 455. Firstactuator 417B is situated within channel 413B, and includes cams 423,427 as described above with reference to FIG. 11A. Below cam 427, firstactuator 417B includes an engagement portion 457 that extends throughopening 447 into cavity 422. Spring 453 is positioned between end 445 ofchannel 413B and engagement portion 457, and biases first actuator 417Bupwardly into the position shown in FIG. 11B. Second actuator 419B issituated within channel 415B, and includes cams 431, 435 as describedabove. Second actuator 419B also includes an engagement portion 459 thatextends from below cam 435, through opening 451, and into cavity 422.Spring 455 biases engagement portion 459 (and second actuator 419B)upwardly into the position shown in FIG. 11B.

[0061] When plug 18A is inserted into cavity 422 of receptacle 422B, noelectrical connections are made between plug 18A and receptacle 422Buntil plug 18A approaches the seated position. More specifically, asplug 18A reaches the lower portion of cavity 422, a pair of grooves (notshown) formed in plug 18A receive engagement portions 457, 459. Whenengagement portions 457, 459 reach a stop surface (not shown) formed inthe grooves, further downward movement of plug 18A into cavity 422 movesfirst actuator 417B and second actuator 419B downwardly against thebiasing force of springs 453, 455, respectively. This downward movementof first actuator 417B and second actuator 419B causes cams 423, 427,431, and 435 to respectively move detent contacts 448A, 452A, 446A, and450A into electrical connection with plug 18A as described above. Whenplug 18A is withdrawn from cavity 422, springs 411 and 453, 455 urgedetent contacts 448A, 452A, 446A, and 450A, first actuator 417B, a andsecond actuator 419B back into the upward position shown in FIG. 11B. Itshould be understood that springs 453, 455 may be optional, since thebiasing force of springs 411 may, without any other return mechanism,cam first actuator 417B and second actuator 419B into the upwardpositions.

[0062]FIG. 11C shows yet another receptacle 422C according to thepresent invention. Receptacle 422C is similar to receptacle 422B in thatit includes a two-piece actuator that does not extend out of theassembly. Unlike receptacle 422B, receptacle 422C includes a two-pieceactuator that is engaged by stop 40 of plug 18A. More specifically,first half 402C includes a modified channel 413C that terminates at alower end 445 and at an upper end 461. An opening 463 is formed adjacentupper end 461 between channel 413C and enlarged diameter portion 424 ofcavity 422. Second half 404C similarly includes a modified channel 415Cthat terminates at an upper end 465 and includes an opening 467.

[0063] First actuator 417C of receptacle 422C is situated within channel413C, and includes cams 423, 427 as described above with reference toFIG. 11A. First actuator 417C further includes an elongated body portion469 that extends from cam 423 and terminates at an engagement portion471 that extends through opening 463 into enlarged diameter portion 424of cavity 422. Second actuator 419C is similarly situated within channel415C, and includes cams 431, 435 as described above. Second actuator419C also includes an engagement portion 473 that extends from above cam431, through opening 467, and into enlarged diameter portion 424.

[0064] When plug 18A is inserted into cavity 422 of receptacle 422C, noelectrical connections are made between plug 18A and receptacle 422Cuntil plug 18A approaches the seated position. More specifically, asplug 18A reaches the lower portion of cavity 422, a pair of openings orgrooves (not shown) formed in stop 40 of plug 18A receive engagementportions 471, 473. When engagement portions 471, 473 reach a stopsurface (not shown) formed in the grooves, further downward movement ofplug 18A into cavity 422 moves first actuator 417C and second actuator419C downwardly. This downward movement of first actuator 417C andsecond actuator 419C causes cams 423, 427, 431, and 435 to respectivelymove detent contacts 448A, 452A, 446A, and 450A into electricalconnection with plug 18A as described above. When plug 18A is withdrawnfrom cavity 422, springs 411 urge detent contacts 448A, 452A, 446A, and450A, first actuator 417C, and second actuator 419C back into the upwardposition shown in FIG. 11C.

[0065] The foregoing description of the invention is illustrative only,and is not intended to limit the scope of the invention to the preciseforms set forth. Although the invention has been described in detailwith reference to certain illustrative embodiments, variations andmodifications exist within the scope and spirit of the invention asdescribed and defined in the following claims. For example, one skilledin the art could readily adapt interfaces, pendants, and other equipmentwith conventional connectors so that the various pieces of equipment aremodular and easily replaceable. Moreover, the entire support body of anequipment support device according to the present invention could beformed from flexible, gooseneck material to provide additionalflexibility. It should be further understood, that the basic concept ofthe present invention may be adapted to other uses such as with headwallunits, power columns, overbed tables, and wheelchairs.

What is claimed is:
 1. An electrical connector, including: a receptaclehaving a first end, a second end, a cavity extending toward the secondend from an opening at the first end, a first contact extending into thecavity at a first distance from the opening, and a second contactextending into the cavity at a second distance from the opening, thesecond distance being greater than the first distance; and a plug beingremovably received by the receptacle cavity, the plug having a body anda stop for limiting the extent to which the body may be inserted intothe cavity, thereby defining a seated position, the body including firstand second contacts that contact the first and second receptaclecontacts, respectively, as the body approaches the seated position. 2.The connector of claim 1, wherein the cavity is substantiallycylindrical.
 3. The connector of claim 1, wherein the receptaclecontacts are detents biased toward a central axis of the cavity.
 4. Theconnector of claim 1, wherein the body is substantially cylindrical. 5.The connector of claim 4, wherein the stop is disposed adjacent one endof the body, the stop being annular and having a diameter that isgreater than a diameter of the body.
 6. The connector of claim 5,wherein the cavity includes a portion adjacent the opening for receivingthe stop having a diameter substantially corresponding to the stopdiameter.
 7. The connector of claim 4, wherein the plug contacts areannular.
 8. The connector of claim 4, wherein each of the plug contactsincludes a ring portion having a diameter that is greater than adiameter of the body, the ring portions cooperating with the receptaclecontacts to resist removal of the plug from the receptacle when the plugbody is in the seated position.
 9. The connector of claim 1, the bodyfurther including a first insulator between the first and secondcontacts.
 10. The connector of claim 1, the receptacle further includinga third contact extending into the cavity at a third distance from theopening, and a fourth contact extending into the cavity at a fourthdistance from the opening, the third distance being greater than thesecond distance and the fourth distance being greater than the thirddistance, the plug body further including third and fourth contacts thatcontact the third and fourth receptacle contacts, respectively, as thebody approaches the seated position.
 11. The connector of claim 10,wherein the plug body is cylindrical and the plug contacts are annular,the plug further including a first annular insulator disposed betweenthe first and second plug contacts, a second annular insulator disposedbetween the second and third plug contacts, and a third annularinsulator disposed between the third and fourth plug contacts.
 12. Theconnector of claim 11, wherein each of the first, second, and thirdannular insulators has a length that is different from the lengths ofthe other annular insulators.
 13. The connector of claim 12, whereineach of the first, second, and third annular insulators includes atleast one of a first insulator section and a second insulator section,the first and second insulator sections having different lengths. 14.The connector of claim 10 wherein the distance between the first andsecond plug contacts is different from the distance between the secondand third plug contacts.
 15. The connector of claim 14, wherein thedistance between the third and fourth plug contacts is different fromthe distance between the first and second plug contacts and differentfrom the distance between the second and third plug contacts.
 16. Theconnector of claim 1, wherein the plug further includes a tip disposedadjacent a first end of the body for guiding the plug into thereceptacle, the stop being disposed at a second end of the body oppositethe first end.
 17. An equipment support for use with a patient assistapparatus having a signal source providing a first and a second signal,the support including: a receptacle adapted to mount to the patientassist apparatus, the receptacle including a first contact adapted toreceive the first signal, a second contact adapted to receive the secondsignal, and a cavity; and a support body having an equipment end and aplug for being removably inserted into the cavity, the plug having abody including a first contact connected to a first conductor and asecond contact connected to a second conductor, the first and secondconductors extending to the equipment end of the support body and beingadapted for connection to a first piece of equipment mounted to theequipment end of the support body; wherein the first plug contactcontacts the first receptacle contact and the second plug contactcontacts the second receptacle contact only when substantially theentire plug body is inserted into the cavity.
 18. The support of claim17, wherein the receptacle cavity is substantially cylindrical.
 19. Thesupport of claim 17, wherein the receptacle contacts are detents. 20.The support of claim 17, wherein the support body is substantiallycylindrical.
 21. The support of claim 20, wherein each of the plugcontacts includes a ring portion having a diameter that is greater thana diameter of the body, the ring portions cooperating with thereceptacle contacts to resist removal of the plug from the receptaclewhen substantially the entire plug body is inserted into the cavity. 22.The support of claim 17, wherein the support body further includes afirst section that is telescopically connected to a second section. 23.The support of claim 17, further including a flexible portion extendingfrom the equipment end of the support body.
 24. The support of claim 23,wherein the first and second conductors are adapted for connection to asecond piece of equipment mounted to a free end of the flexible portion.25. The support of claim 17, wherein the plug body is substantiallycylindrical.
 26. The support of claim 25, wherein the plug furtherincludes an annular stop having a diameter that is greater than adiameter of the plug body, the stop being seated within an enlargeddiameter portion of the cavity when substantially the entire plug bodyis inserted into the cavity.
 27. The support of claim 17, wherein theplug contacts are annular.
 28. The support of claim 17, wherein thecavity has a central axis, the first receptacle contact extending intothe cavity at a first location along the central axis, and the secondreceptacle contact extending into the cavity at a second location alongthe central axis.
 29. The support of claim 28, wherein the receptaclefurther includes a third contact extending into the cavity at a thirdlocation along the central axis, and a fourth contact extending into thecavity at a fourth location along the central axis, the plug bodyfurther including third and fourth contacts that contact the third andfourth receptacle contacts, respectively, only when substantially theentire plug body is inserted into the cavity.
 30. The support of claim29, wherein the plug body is cylindrical and the plug contacts areannular, the plug further including annular insulators separating theplug contacts.
 31. The support of claim 29, wherein the second locationis a first distance from the first location, the third location is asecond distance from the second location, and the fourth location is athird distance from the third location, each of the first, second andthird distances being different from the other distances.
 32. A hospitalbed, including: a frame for supporting a patient, the frame including areceptacle having a first contact connected to a first signal, a secondcontact connected to a second signal, and a cavity; and an equipmentsupport having a body with a first equipment mount adjacent one end, aplug connected to the other end for removable insertion into thereceptacle cavity, and a pair of conductors extending from the firstequipment mount to the plug, the plug including a first contactconnected to one of the conductors and a second contact connected to theother conductor; wherein the first and second plug contacts respectivelyengage the first and second receptacle contacts, thereby providing thefirst and second signals through the conductors to the equipment mount,as the plug is inserted into the cavity.
 33. The bed of claim 32,wherein the frame includes a plurality of receptacles to permitplacement of the equipment support at a plurality of different locationsabout the bed.
 34. The bed of claim 32, wherein each of the receptaclecontacts includes an electrically conductive ball and a spring thatbiases the ball into the cavity.
 35. The bed of claim 34, wherein eachof the balls is disposed within a respective bore formed in thereceptacle.
 36. The bed of claim 34, wherein each of the plug contactsincludes a ring portion having a diameter that is greater than adiameter of the plug, the ring portions cooperating with the balls toresist removal of the plug from the receptacle when the plug is fullyinserted into the cavity.
 37. The bed of claim 32, wherein the supportbody is a pole.
 38. The bed of claim 32, wherein the support bodyfurther includes a first section that is telescopically connected to asecond section.
 39. The bed of claim 32, further including a flexibleportion extending from the one end of the support body.
 40. The bed ofclaim 39, wherein the first and second conductors extend to a secondequipment mount connected to a free end of the flexible portion.
 41. Thebed of claim 40, further including an interface connected to the firstequipment mount and a pendant connected to the second equipment mount.42. The bed of claim 32, wherein the plug further includes a stop thatengages the receptacle to prevent further insertion of the plug into thecavity when the plug is fully inserted into the cavity.
 43. The bed ofclaim 32, wherein the plug includes a body having an outer surface, theplug contacts being annular and protruding from the outer surface. 44.The bed of claim 32, wherein the receptacle further includes a thirdcontact and a fourth contact, and the plug further includes a thirdcontact and a fourth contact that contact the third and fourthreceptacle contacts, respectively, as the plug is inserted into thecavity.
 45. The bed of claim 44, wherein the plug contacts are separatedby insulators.
 46. The bed of claim 44, wherein the plug contacts areunequally spaced apart from one another along a length of the plug toprevent simultaneous contact between the plug contacts and theirrespective receptacle contacts when the plug is being inserted andremoved from the cavity.
 47. A patient assist apparatus, including: aframe; a receptacle mounted to the frame, the receptacle havingelectrical contacts that receive a signal; a pole having a piece ofequipment connected to one end and a plug connected to the other end,the plug having electrical contacts connected to the equipment that arein electrical communication with the receptacle contacts when the plugis inserted into the receptacle, thereby providing the signal to theequipment.
 48. The apparatus of claim 47, wherein the frame includes aplurality of receptacles to permit placement of the pole at a pluralityof different locations.
 49. An electrical connector, including: areceptacle having a cavity and a first conductor adjacent the cavity;and a plug having a second conductor adjacent an outer surface of theplug; wherein a signal on the first conductor is coupled to the secondconductor when the plug is substantially fully inserted into thereceptacle cavity.
 50. The connector of claim 49, wherein the cavityextends from an opening in one end of the receptacle toward another endof the receptacle.
 51. The connector of claim 50, wherein the cavity issubstantially cylindrical.
 52. The connector of claim 49, wherein theplug includes a stop for limiting the extent to which the plug may beinserted into the cavity, thereby defining a seated position, the signalbeing coupled from the first conductor to the second conductor when theplug is in the seated position.
 53. The connector of claim 52, whereinthe stop is disposed adjacent one end of the plug, the stop beingannular and having a diameter that is greater than a diameter of theplug.
 54. The connector of claim 49, wherein the plug is substantiallycylindrical.
 55. The connector of claim 50, wherein the cavity includesa portion adjacent an opening of the cavity for receiving the stop, thecavity portion having a diameter substantially corresponding to adiameter of the stop.
 56. The connector of claim 49, wherein the plugfurther includes an annular ring that has an increased diameter relativeto another diameter of the plug, and the receptacle includes a detentfor cooperating with the ring to resist removal of the plug from thereceptacle when the plug is inserted into the cavity.
 57. The connectorof claim 49, wherein the first conductor forms a first loop about thecavity and the second conductor forms a second loop within the plug. 58.The connector of claim 57, wherein the first and the second loops aresubstantially planar when the plug is substantially fully inserted intothe cavity.
 59. The connector of claim 49, wherein the receptaclefurther includes a third conductor adjacent the cavity, and the plugfurther includes a fourth conductor adjacent the outer surface of theplug, a second signal on the third conductor being coupled to the fourthconductor when the plug is inserted into the receptacle cavity.
 60. Theconnector of claim 59, wherein the first conductor forms a first loopabout the cavity, the second conductor forms a second loop within theplug, the third conductor forms a third loop about the cavity, and thefourth conductor forms a fourth loop within the plug.
 61. The connectorof claim 60, wherein the first and the second loops are substantiallyplanar and the third and the fourth loops are substantially planar whenthe plug is substantially fully inserted into the cavity.
 62. Anelectrical connector, including: a receptacle having a first end, asecond end, a cavity extending toward the second end from an opening atthe first end, a first contact movably supported by the receptacle, anda second contact movably supported by the receptacle; a plug beingremovably received by the receptacle cavity, the plug including firstand second contacts; and an actuator supported by the receptacle, theactuator including a first cam disposed adjacent the first receptaclecontact, a second cam disposed adjacent the second receptacle contact,and an engagement portion configured to be contacted by the plug as theplug approaches a seated position; wherein further movement of the plugto the seated position moves the engagement portion, thereby causing thefirst cam to move the first receptacle contact into engagement with thefirst plug contact, and the second cam to move the second receptaclecontact into engagement with the second plug contact.
 63. The connectorof claim 62, wherein the engagement portion extends beyond the secondend of the receptacle.
 64. The connector of claim 62, wherein theengagement portion extends into the cavity adjacent the second end ofthe receptacle.
 65. The connector of claim 62, wherein the engagementportion extends into the cavity adjacent the first end of thereceptacle.
 66. The connector of claim 62, wherein a portion of theactuator is disposed within a channel formed in the receptacle.